﻿<p><em>IfcSurfaceStyle</em> is an assignment of one or many surface style elements to a surface, defined by subtypes of <em>IfcSurface</em>, <em>IfcFaceBasedSurfaceModel</em>, <em>IfcShellBasedSurfaceModel</em>, or by subtypes of <em>IfcSolidModel</em>. The positive direction of the surface normal relates to the positive side. In case of solids the outside of the solid is to be taken as positive side.</p> 

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NOTE&nbsp; The surface style is often referred to as material definition in rendering applications.
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NOTE&nbsp; Corresponding ISO 10303 entity: surface_style_usage and surface_side_style. Please refer to ISO/IS 10303-46:1994 for the final definition of the formal standard. The surface style definition in regard to support of rendering has been greatly expanded beyond the scope of ISO/IS 10303-46.
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HISTORY&nbsp; New entity in IFC2x.
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